CHROMiX ColorNews Issue #19 - Color Management Myths 26-28
Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues.
C H R O M i X C O L O R N E W S
Several Quick Notes of Interest:
** FREE CHROMiX Color Management Utility Kit when you buy either an Eye-One Pro solution or an X-Rite Pulse ColorElite solution. See ad below.
** Big Price Drop on GretagMacbeth Eye-One products AND a further $200 off Eye-One solutions??
** Purchase an Eizo ColorEdge LCD monitor and get either half off a ColorEyes Display bundle, or get one absolutely free!! (offer varies depending on monitor model) This bundle is valued at $319, and is currently the most highly regarded LCD monitor calibration software & instrument on the market. See detail below.
** Got an old Eye-One? Wishing you could justify the purchase of one of the new ones with all the bells and whistles? Well, now's the time! GretagMacbeth, in discussions with CHROMiX, is preparing to launch it's new Customer Loyalty Program!
** 3 more Color Myths - an article written by CHROMiX President Steve Upton
Table of Contents
1. CHROMiX News
Since our last ColorNews Issue #18 on June 2, here's what's going on at CHROMiX:
Rick Hatmaker of CHROMiX wrote an article for Digital Imaging Techniques (August issue) evaluating the GretagMacbeth Eye-One product line as well as the the X-Rite Pulse ColorElite solution. You may find this useful if you're shopping for either product or looking to upgrade. Find the article at: Click Here
Anne Taylor of CHROMiX will be speaking at this year's BioComm conference on July 24th in Portland, OR, about color management and workflow for the field of BioCommunications. Interestingly, most conference attendees are using the Adobe Creative Suite and have overwhelmingly requested color management as a key focus and emphasis. Workflow and color management are particularly problematic in the Biocommunications field due to the wide range of input and output devices used in medicine and the life sciences.
We've had a big price drop on Eye-One Photo, Proof, XT and others. Nothing like a summer sale!
CHROMiX is continuing to offer the training class 'PHOTOSHOP DIGITAL WORKFLOW with COLOR MANAGEMENT'. It is a one day workshop being held August 18 and September 21, from 9:30 am - 4:40 pm, at the Seattle Evolve facility, for $300. Recent attendees have mentioned how effective this class was for them. It could be for you too. Please join us. For more details follow this link:
Steve Upton's Webinar for the IPA "An Introduction to Color Management" on July 13th was very well received! If you missed it, you can still catch part two of this Color Management for the Creative Community series. Part two is called 'Photoshop and Color Accuracy', and is scheduled for Wednesday, August 3rd at 1:00 PM Eastern. Steve will cover Photoshop essentials for accurate color matching, including:
- Manage missing profiles when opening files
For more information, or to register:
ColorThink 2.2b15 beta is now available. It is a free update to the current ColorThink software. We continue to add fixes and look for feedback from our users. Download a copy, give it a try, and let us know what you think.
CHROMiX at Print05 in Chicago. Yes we'll be there and we'll be showing off new versions of our software. We haven't determined which booth we'll be in yet so stay tuned! (we'll have a newsletter before Print05 giving all the details)
Steve Upton of CHROMiX is serving a second year on the GATF conference's advisory panel. The dates for the popular color management conference are December 4-6, 2005 in Phoenix AZ. A call for speakers has been issued, so interested speakers should contact Gwen Martin at the GATF.
The number of users and topics of discussion continue to grow at our ColorForums website. Check it out if you are looking for answers to technical problems. It's free!
Finally, please let us know how you like the new ColorNews RSS Feed service on our home page. We welcome your feedback.
Color, Product & Industry News
GretagMacbeth Customer Loyalty Program - this is just being finalized as we "went to press".
GretagMacbeth has released the long-awaited ProfileMaker Packaging software. This extension to the ProfileMaker line is intended for the particular challenges of the packaging industry and includes the ability to create n-color profiles (profiles where the ink is in any order, up to 10 channels) and their patent-pending GOP profiling technology. GOP (Generic Output Profiler) allows the replacement of an ink, and the recalculation of the profile without having to perform an additional press run. This is going to be a boon for the flexo market. GretagMacbeth will have product information as well as an interactive training piece available on their site within the next day or so:
In June, IPA announced the results of the 2005 Color Proofing and Workflow RoundUP. EFI ColorProof and GMG scored well for Proofing, and other RIPS were not far behind. Dr. Abhay Sharma, author of Understanding Color Management and a respected professor at Western Michigan University, conducted the event. The results are available on a CD for a nominal fee, and is well worth it, as this is one of the more legitimate product comparisons you'll find.
Unless you live in a cave you probably already know this... Adobe is planning to buy Macromedia. More details at
Apple has announced the plan to shift processor supplier from IBM to Intel. On June 6, 2005 Steve Jobs announced this decision at his Keynote speech at Apple's 2005 Worldwide Developer Conference. The first Intel processors should ship with Macs starting in 2006 and the entire product line should be running Intel by 2007. (All CHROMiX software products will be supported on the new platform.)
Microsoft announced PowerToy, an upcoming RAW viewer add-on for Windows XP that enables the handling of Canon and Nikon RAW formats directly within Windows. Microsoft will also be adding extensive RAW format support through a codec architecture for Longhorn, the next major release of Windows due in 2007.
ColorBurst will announce (on Friday 7/22) version 4 X-Proof and X-Photo RIP software that will support the Epson 4800. They will have an FTP site for downloads. ColorBurst mentioned that a free updater will be posted to the their website next week. ColorBurst has also recently been approved as part of two SWOP certified proofing systems on both Mac and PC platforms. This is the fifth SWOP certified proofing system for ColorBurst in the last two years.
GTI, maker of controlled lighting and viewing stations, has introduced several new models which reflect the ongoing shift toward wide-format and digital imaging. They have expanded the VPI Vertical Print Inspectors to include vertical (poster) format. GTi has also added the availability of rotary controlled dimming or digital dimming on their 24", 36", and 48"" overhead luminaires.
SHOWS & EVENTS
September 8-10, 2005, PMA Fall Imaging Conference and Mini Trade Show at Manchester Grand Hyatt, San Diego, CA.
September 9-15, 2005, PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only once every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
September 11-14, 2005, Seybold Chicago at Hyatt Regency McCormick Place, Chicago, IL.
September 28-29, 2005, Digital Imaging '05 at Hyatt Regency San Francisco Airport, CA.
September 28 - March 1, 2005, SGIA Specialty Printing & Imaging Technology Show, New Orleans, LA.
November 29 - December 2, 2005, Seybold San Francisco at The Palace Hotel, San Francisco, CA.
December 4-6, 2005, PIA/GATF Color Management Conference at The Pointe Hilton Tapatio Cliffs Resort, Phoenix, AZ. This is the only US show with exclusive focus on color management technology. Hear about the latest tools, workflows, and trends in producing high-quality color.
ColorFAQ - 3 more Color Myths
Myth #26: Graphing profiles to see their gamut gives pretty much the same results in the different tools that are available.
ColorThink plots gamuts using the device->Lab (ie CMYK->Lab) "proofing" part of the profile. Like when you soft proof, we ask the profile "if I send 100% Cyan, what color will I get?" - only we ask it for a large number of these colors and we get a good estimation of the behavior of the device. If you built the profile yourself and have access to the original measurements, you can plot them along with the ColorThink profile gamut and they will match up quite closely (if it's a good profile). When we do this "proofing" conversion we use the absolute colorimetric rendering intent which gives us accurate paper whites and ink blacks.
The ONLY way to show the actual gamut of the _device_ is to use the Absolute Colorimetric intent when calculating. This pulls the white down to paper-white and shades it accordingly. None of the methods of viewing profiles in the ColorSync Utility allow this.
The ColorSync utility allows you to view the "gamuts of profiles" by either clicking on them in the profile list (which shows the perceptual mapping) or clicking on the various A2Bx tags when you open a profile. When you click on these tags in the profiles, the CSU shows you the perceptual, saturation and relative colorimetric gamuts. What do they represent? well, they show how colors in device-space (CMYK, RGB, etc) will appear when converted through the profile. Does this mean anything? sort of, but only to a very experienced user. People typically want to know 1) how is my device performing and 2) how is my profile performing when printing? (which is the opposite, Lab->device conversion)
So, ColorThink answers #1 (and is the only grapher I know of that does it this way, why I don't know) and graphing a color list or image and applying a profile to get vectors answers #2. The CSU doesn't answer either of these questions... not that what it's doing is technically incorrect.... well perhaps it is:
- each "unit" in Lab is supposed to represent the smallest color shift the eye can see - in any direction (lightness, saturation, hue). The lightness axis L goes from 0-100 while the a and b axes go from -128 to 127. This means the box defined by the ICC for Lab is not a cube but is wider than it is tall. There is no valid reason to stretch the vertical L axis to be the same size as the widths of a and b but many graphers do this including the CSU... This results in "tall" gamuts and ColorThink's are "flatter". As far as I can determine, flatter is correct yet most other graphing tools I've seen stretch the Lab space into a cube, producing tall skinny gamut volumes that don't make sense (at least to me)
Other graphers like Monaco, GretagMacbeth and others plot what I call the "rendered gamut" of profiles (as opposed to the device gamut). Using this method, Lab values are converted through the profile to device colors and then back to Lab. If very saturated colors are chosen at the outset then this round-trip method will squish them into gamut and then a gamut volume can be graphed. This volume can be useful but does not describe the device behavior alone - it really shows what the profile will give you if used to print to the device (and specifically how the very saturated colors will print). This may seem like splitting hairs but it's not. Many printers receive CMYK files separated by unknown profiles. A device gamut will describe the maximum space these images can occupy, a rendered gamut will not and, in fact, some image colors may appear outside of the rendered gamut. Another way to think of this is with the example of ink limiting. If you build a CMYK profile that has a total ink limit of 200% you will probably limit the gamut of files printed using that profile. When graphed in ColorThink you will see the gamut of the device, all the way up to 400% coverage. In other tools you will see the rendered gamut, which will be smaller, especially in the darker colors.
ColorThink Pro, which we are working on right now will allow both graphing methods so you can compare the profile's printing capabilities with the device's overall capabilities. The "normal" ColorThink will continue to graph device gamuts. They are the simplest to understand and jibe well with graphs of the device measurements used to build the profile.
A bit long-winded I know but that's the way it is with color..I hope this helps.
Myth #27: Why would anyone ever want to choose a working space that is larger than you can print?
This is a classic question and one that we receive only slightly more often than "Why does my printer keep recommending such small working spaces?"
The roots of these schools of thought are in the perspective of each user and how they tend to want to recommend (push) their workflow to other people. In studying color reproduction challenges over the years, I have broken workflows down to three distinct groups (I am exaggerating them a little):
- Input Centric - this is where people want to capture as much of the original film (or scene) as possible. They choose large working spaces (much larger than the monitor gamut) and archive high-bit images for the day when printers catch up with their desires. Monitors, printers and presses are necessary evils that all degrade the appearance of their work. If they have the ability they will fill a whole CD with one scanned image. You might guess that this is where photographers often reside.
- Output Centric - this is where the final print is the deciding factor in workflow decisions. Working spaces like ColorMatch are considered plenty big enough to contain all the colors one would want to print. So working spaces are chosen that will contain the gamut of a press and nothing more. Much of their work is done in CMYK (in-gamut by definition) and they wonder why anyone would bother capturing color that can't be printed. As you can imagine, prepress and printing folks are in this group.
- Display-Centric - this is where people just want what's printed to match what's on the screen. Computer artists, 3D artists, video editors and consumers tend to fall into this group. All work headed for the web also falls in this category. sRGB is typically chosen as the working space as it tends to match the display gamut fairly closely. It doesn't contain any more colors than the display can show so there are fewer surprises.
The truth is that each of us will find ourselves in these different roles at some time. There's nothing wrong with being in any of the groups and people may change groups depending on their budget or project. It's fair to say, however that folks who are entrenched in any one group have a lot of trouble understanding the other groups.
Ever try to get an offset printer to try to understand your photographic decisions? or vice versa?
So if John is an "Input Centric" and your are an "Output Centric" you will probably never see eye-to-eye on working spaces AND you may each be using spaces that are good for your respective pursuits.
In color management there is often no single correct way to do things. What we do suggest is a few things that will apply to all:
- choose a working space that is just large enough to contain your imagery; any bigger and you're wasting space.
Myth #28: The PowerBook G4 displays 16.7 million colors (or any display, for that matter)
This is not true. Don't confuse RGB number combinations with the number of perceivable colors.
I can send 16.7 million different RGB NUMBER combinations to a PowerBook display (3 channels with 8 bits per channel) but it will only display 518,733 different colors. This means that 16,258,483 of the RGB numbers are basically "wasted". Another way of looking at this is to say that the entire gamut of 518,733 colors is chopped into 16.7 million separately addressable "chunks". Problem is, the difference between each of these chunks is smaller than is perceivable by humans. So if you glom chunks together until each blob is just barely perceivably different than the next, you'll end up with 518,733 of them.
That explanation is a bit of a stretch but sometimes it helps to break these things down to understand them. (pun intended)
This confusion is another example of the difference between RGB and CMYK values and actual colors.
Another example of this is with CMYK devices. I can send 100,000,000 CMYK values to print on newsprint (100x100x100x100). Does that mean I'm going to get that many actual colors? No, of course not. If I send those CMYK values to a sheet-fed press on glossy coated paper will I get that many colors? No, but I'll get more than I did from newsprint. I'd probably see even more from an inkjet. While I can address the colors on a press using CMYK combinations, each CMYK combination will not produce a unique color.
Thanks for reading,
For previous ColorNews articles follow this link:
Entire Contents of CHROMiX ColorNews (c)2005 CHROMiX, Inc.